Question

The relative time ratings of exercises are shown in square brackets after each exercise number. On average, an exercise rated [10] will take you twice as long as one rated [5]. Sections of the text that should be read before attempting an exercise will be given in angled brackets; for example, <1.3> means you should have read Section 1.3, Under the Covers, to help you solve this exercise. 2.1 [5] For the following C statement, what is the corresponding MIPS assembly code? Assume that the variables f, g, h and i are declared as 32-bit integers. f = g + (h - 5); 2.3 [5] <S$2.2, 2.3> For the following C statement, what is the corresponding MIPS assembly code? Assume that the variables f, g, h, i, and j are assigned to registers $s0, $$1, $s2, $s3, and $s4, respectively. Assume that the base address of the arrays A and B are in registers $s6 and $s7, respectively. B[8]Ai-j ]: 2.4 [5] <$2.2, 2.3> For the MIPS assembly instructions below, what is the corresponding C statement? Assume that the variables f, g, h, i, and j are assigned to registers $$0, $ s1, $s2, $s3, and $s 4, respectively. Assume that the base address of the arrays A and B are in registers $$6 and $s7, respectively s11 $t0, $s 0. 2 add $t0. $s6, $t0 $11 $t1, $s1, 2 f #$t0 #$t0 & A Cf] g4 # $t1 # $t1 &BEg] #f=A[f] 4 add $t1, $s 7, $t1 1w $s0, 0 ($t0) addi $t2. $t0, 4 $to, 0( $t2) add $t0, $t0, $s0 $t0, 0($t1) 1w SW 2.5 [5]<S$2.2, 2.3> For the MIPS assembly instructions in Exercise 2.4, rewrite the assembly code to minimize the number if MIPS instructions (if possible) needed to carry out the same function.

Answer 1

5); 2o) 5, 2e- /1 to $50 Subi $to $s 2 5 S Cu-s add So

S ase Address r A A Ci- Code c 3 2 addi Zero $ti /$ $to -j 4Ci-) $to Sub to $to SII to= $to 2 $to 후to add to $to to Sw FA

s0 C&) Gase Address (4$S7 $S Gase Address f x 4 / to 2. $to SI $5$to to= add $ Si SI 2 add So f= AC $t2 $to4 oCto) t $to addi A A add $to AC キto to50 $to SW + A 工oc A